【摘要】 位于准噶尔盆地西北缘前陆冲断带北段的哈拉阿拉特山,以往认为是一个典型的逆冲推覆构造带。笔者通过野外地质调查和对地震与大地电磁测深(MT)资料的综合解释研究,发现该区总体表现出走滑—冲断复合构造特征。其形成受控于达尔布特断裂在不同时期不同性质的活动,主要经历了两个阶段:二叠-三叠纪是以逆冲推覆为主兼具走滑的斜向冲断,形成该区以逆冲推覆构造为主要特征的走滑—冲断构造;侏罗纪以来主要以左行压扭走滑变形为主,沿达尔布特断裂变形强烈,形成花状构造,并在一定程度上改造了前期形成的逆冲推覆构造,但强度较弱。因此,目前在哈拉阿拉特山地区所见到的构造现象实际上是二叠纪至三叠纪斜向冲断和侏罗纪以来的压扭走滑两期构造变形的叠加样式,总体构成走滑—冲断复合构造。这一地质构造模型的建立对地震解释具有指导作用,同时指出逆冲推覆构造下盘的隐伏背斜未经后期走滑改造,是油气勘探的重要方向。更多还原

【Abstract】 The area of Hala′alate mountains, located in the north segment of the foreland thrust belt of the northwestern margin of the Junggar basin, was once considered to be a typical foreland thrust belt. Based on recent field geological survey and the comprehensive interpretations of seismic and MT exploring data, it was demonstrated that the regional evolution of Hala′alate mountains mainly experienced two stages. The first stage of deformation was thrust-nappe structures, accompanied by strike-slipping in Permian to Triassic, and the second stage of deformation was sinistral strike-slipping from Jurassic, revealed by the positive flower structure. Therefore, the existed structural styles in the area of Hala′alate mountains were, in fact, a superimposed structure, or a strike-slip——thrust composite structure. The Daerbute fault, as a west boundary fracture of the mountain area, thrusted towards the southeast in Permo-Triassic accompanied with subduction of the Altai Ocean and followed continent-arc collision. From Jurassic, it became a sinistral strike-slip fault. It was believed that the identification of the geological structure style should be helpful not only to interpretation of the seismic data, but also to the petroleum exploration. The anticlinal structures in the lower plate of the Daerbute fault should be potentials for oil and gas exploration, since they might be undeformed during the strike-slipping of the Daerbute fault in the Yanshanian—Himalayan movements.更多还原